The news is a major breakthrough in the unprecedented two-week struggle to find out what happened to Flight 370, which disappeared shortly after takeoff from Kuala Lumpur to Beijing with 239 passengers and crew aboard on March 8.

Dressed in a black suit, Najib announced the news "with deep sadness and regret" in a brief news conference late today.

He said Malaysia Airlines has informed the families of passengers of the plane's fate.

Najib said the information was based on an unprecedented analysis of satellite data from Inmarsat.

Ships rushed to the location of floating objects spotted today by Australian and Chinese planes in the southern Indian Ocean close to where multiple satellites have detected possible remains of the lost Malaysian airliner.

One ship was carrying equipment to detect the plane's vital black box, but it remained uncertain whether the vessels were approaching a successful end to the search or another frustrating dead end.

Australian Prime Minister Tony Abbott called his Malaysian counterpart, Najib Razak, and informed him about objects that had been found in the search, Malaysian national news agency Bernama reported. Najib was scheduled to hold a news conference late today.

Earlier, Abbott said in Canberra that the crew on board an Australian P3 Orion had located two objects in the search zone — the first grey or green and circular, the second orange and rectangular. The crew was able to photograph the objects, but it was unclear if they were part of an aircraft.

An Australian navy supply ship, the HMAS Success, headed into the area to get a closer look but weather conditions and visibility were poor, according to John Young, manager of the Australian Maritime Safety Authority's emergency response division.

"You may find that we will be doing this for maybe three or four more days before we are confident that we've either found all the objects there, or if they are there, we simply cannot find them," Young said.

Data marker buoys dropped into the search zone by aircraft showed currents were moving in different directions, which Young said "is an indication of water that's not going anywhere in particular, which is better for searching — it means we don't have to move the search area a lot."

Separately, the crew aboard one of two Chinese IL-76 aircraft combing the search zone observed two large objects and several smaller ones spread across several square kilometers (miles), Xinhua News Agency reported. At least one of the items — a white, square object — was captured on a camera aboard the plane, Chinese Foreign Ministry spokesman Hong Lei said.

"We are still racing against time," Hong said at a ministry briefing. "As long as there is a glimmer of hope, our search efforts will carry on."

China has redirected the icebreaker Snow Dragon toward the latest find, and that ship was due to arrive early Tuesday. Six other Chinese ships have been directed toward the search zone, about 2,500 kilometers (1,550 miles) southwest of Perth, along with 20 fishing vessels that have been asked to help, Hong said.

Relatives of passengers aboard the missing Boeing 777-200 were closely following news reports of the latest sightings, desperate for any word on the fate of loved ones.

"We're eager to learn more about this," said Wang Zhen, who is staying at a hotel near Beijing. His father and mother, Wang Linshi and Xiong Yunming, were both aboard Malaysia Airlines Flight 370 as part of a group of Chinese artists touring Malaysia.

Satellite images and data released by Australia, China and France in recent days have identified possible debris in the area that may be linked to the disappearance of the plane on March 8 with 239 people on board — two-thirds of them Chinese.

The ocean depth in the search area ranges between 1,150 meters (3,770 feet) and 7,000 meters (23,000 feet), and the U.S. Pacific Command said it was sending a black box locator in case a debris field is located.

The Towed Pinger Locator, which is pulled behind a vessel at slow speeds, has highly sensitive listening capability so that if the wreck site is located, it can hear the black box "pinger" down to a depth of about 20,000 feet (6,100 meters), Cmdr. Chris Budde, a U.S. 7th Fleet operations officer, said in a statement.

"This movement is simply a prudent effort to pre-position equipment and trained personnel closer to the search area so that if debris is found we will be able to respond as quickly as possible since the battery life of the black box's pinger is limited," Budde said.

An Australian navy support vessel, the Ocean Shield, was also moving into the search zone and would arrive in three or four days, a defense official said. The ship is equipped with acoustic detection equipment that can also search for the missing plane's black box.

There was no sign the move was linked to any breakthrough in the mystery of the plane, but rather as a preparation.

"The time for the battery life (of the 'pinger') is potentially only a month," said Jason Middleton, an aviation professor at the University of New South Wales in Sydney. "If debris was found, it would be terrible not have anything on site and waste time" getting a ping detector to the region. "I think they're planning ahead and getting it ready."

The search was given added momentum when a French satellite detected potential debris on Sunday, after Australia and China earlier released satellite images identifying suspect objects.

Australian Transport Minister Warren Truss said the French radar data located the objects about 850 kilometers (520 miles) north of the current search area, and that "we need to check that out as well."

Australian authorities had sent planes and a ship to try to locate a wooden pallet that was spotted on Saturday from a search plane, but the spotters were unable to take photos of it.

Wooden pallets are most commonly used by ships but are also used in airplane cargo holds. Hishammuddin Hussein, the Malaysian defense minister, confirmed Monday the flight was carrying wooden pallets. But he said there was not yet any evidence that the pallets found by the Australians were related to the missing plane.

The southern Indian Ocean is thought to be a potential area to find the jet because Malaysian authorities have said pings sent by the Boeing 777-200 for several hours after it disappeared indicated that the plane ended up in one of two huge arcs: a northern corridor stretching from Malaysia to Central Asia, or a southern corridor that stretches toward Antarctica.

Malaysian authorities have not ruled out any possible explanation for what happened to the jet, but have said the evidence so far suggests it was deliberately turned back across Malaysia to the Strait of Malacca, with its communications systems disabled. They are unsure what happened next.

Authorities are considering the possibilities of hijacking, sabotage, terrorism or issues related to the mental health of the pilots or someone else on board.